INSIVUMEH reported that during 23-24 June explosions at Fuego occurred at a rate of 2-5 per hour, and generated ash plumes that rose 650-950 m above the crater and drifted 10 km SW, W, NW, and N. Lava fountains rose as high as 200 m above the crater, and fed a lava flow that traveled 600 m SE down the Las Lajas (SE) drainage.

In a special bulletin from 1200 on 26 June, INSIVUMEH stated that the tenth episode of effusive activity at Fuego had ended, having lasted for a period of over 30 hours. The report noted that weak explosions continued, producing ash plumes that rose as high as 850 m and drifted 10 km S, SW, and W. Lava flows had advanced to 600 and 800 m in the El Jute (SE) and Las Lajas drainages, respectively. Explosions during 26-28 June generated ash plumes that rose 550-850 m and drifted SSW. Weak shock waves from explosions were detected during 26-27 June, and abundant crater incandescence was visible during 27-28 June.

Geological Summary. Volcán Fuego, one of Central America's most active volcanoes, is also one of three large stratovolcanoes overlooking Guatemala's former capital, Antigua. The scarp of an older edifice, Meseta, lies between Fuego and Acatenango to the north. Construction of Meseta dates back to about 230,000 years and continued until the late Pleistocene or early Holocene. Collapse of Meseta may have produced the massive Escuintla debris-avalanche deposit, which extends about 50 km onto the Pacific coastal plain. Growth of the modern Fuego volcano followed, continuing the southward migration of volcanism that began at the mostly andesitic Acatenango. Eruptions at Fuego have become more mafic with time, and most historical activity has produced basaltic rocks. Frequent vigorous historical eruptions have been recorded since the onset of the Spanish era in 1524, and have produced major ashfalls, along with occasional pyroclastic flows and lava flows.

Source: Instituto Nacional de Sismologia, Vulcanologia, Meteorologia, e Hidrologia (INSIVUMEH)